Guy Fawkes night?

It doesn't have to be short and crappy per se. Just look at Game of Thrones, 10 episodes of 50-60 minutes each with excellent quality. I think it is a bit cheap to say that if it isn't like this, it is subconsequently bad.

 

As the credits roll, you hear a voiceover from a BBC guy saying: "The thing is with Sherlock, you have to watch right to the very end of the credits, or you will miss something." After the credits are finished, you get a glimpse of another British Original Drama (I don't know what it's called) featuring sledges and musketeer-like people. And I would swear that it is Andrew Scott saying 'miss me' during this very short trailer, just before a knife is thrown.

Sherlock Holmes isn't meant to be good looking in the original stories (Conan Doyle even rejected Sidney Paget's drawings at first because he made Holmes 'too hansome'), and Mycroft clearly is an ugly man in the stories.

So the whole Holmes family is not at all fit for a beauty contest  

Very much unlike Sherlock appearently.

Holmes uses cocaine to simulate the feeling he gets when he is working on a crime.

The east wind, where both Mycroft and Sherlock talk about at the end of this episode is a very interesting reference to the 1942 movie 'The Voice of Terror' starring Basil Rathbone. The east wind is used in this movie to describe the coming Nazi forces. 

Holmes' final lines from the movie: "There is an east wind coming, Watson (...) such a wind has never blew on England yet. It will be cold and bitter, Watson, and a good many of us may wither before its blast. But it is God's wind all the less and a greener, better, stronger land will lie in the sunshine when the storm is cleared."

Going back to the '3rd brother question', several Holmes' scholars have deduced that there must have been a 3rd, older, brother. In 'A Scandal in Bohemia' Sherlock Holmes is adressed as 'esq.' or 'esquire' this lead several scholars to believe that the Holmes family was a family of land owners and that the oldest brother must have been the heir to the estate and is still running it. They took Sherrinford as his name, since that was the name that was first used by Conan Doyle as the name of Sherlock Holmes.

The name 'William Sherlock Scott Holmes' was first suggested by Phillip José-Farmer, who created a speculative family tree for the Holmes family (infamously making Holmes an ancestor to Spock...)
 

Indeed, it was a good movie. Some cheap laughs, but okay, I'll forgive them that.

I absolutely do not agree with your 'romantic' view on the relationship between Holmes and Watson in the Granada series. They are portrayed as good friends and absolutely not as lovers. Brett and Hardwick said so themselves. Brett: 'It is about friendship (...) they are both club men, the Victorian era was very much an era of friendship' 
And Watson married Mary Morstan, though off-screen, just as in the books. They probably avoided giving much attention to the marriages of Watson because that one is rather confusing in the stories as well.

I don't think that Jeremy Brett was actually very much like Holmes in his personal life. He said on several occasions that he was more like Watson and that he learned nothing from Holmes to use in his personal life. Of course, his way of acting might have changed him and perhaps may even have encouraged his 'darker sides'.

I think we should see Jeremy Brett apart from Holmes. The problem with actors like him who really define a role is that parts of them might even be projected on the role. Brett himself was very clear about the fact that he wanted to portray Holmes in the way he was written by Doyle.

And yes, Brett was probably bisexual, I don't know who would be unwilling to acknowledge that? 

Sherrinford Holmes...

A nice and subtile nod for the more crazy Holmesians like myself.